I think the proper place to draw the line is the Baltic States and Poland, but not the Ukraine.
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You may be right but not sure Russia would be deterred. The U.S. is not so good at drawing lines anymore. The weak and feckless Obama has no gravitas or credibility and I can’t imagine him initiating any serious form of military retaliation against any aggressive act on the part of Russia. I just don’t see that as a possibility.
After being re-elected, Obama now has “more flexibility” don’t you know. Putin is just beginning to stretch, twist and bend him. We are only in the first inning of this game IMHO.
You would actually have to put US bases there. Tripwire—just like in South Korea.